Vulkan: Split Engine::DoProcessCommands (#120)

Split Engine::DoProcessCommands() into DoProcessCommands() and
GetFrameBufferInfo() for probing FrameBuffer and split it into
DoProcessCommands() and GetDescriptorInfo() for probing SSBO

This commit is a part of PR #101

16 files changed, 161 insertions, 74 deletions

diff --git a/src/dawn/engine_dawn.cc b/src/dawn/engine_dawn.cc
index 159ed10..768e3c2 100644
--- a/src/dawn/engine_dawn.cc
+++ b/src/dawn/engine_dawn.cc
@@ -324,16 +324,7 @@ Result EngineDawn::DoBuffer(const BufferCommand*) {
   return Result("Dawn:DoBuffer not implemented");
 }
 
-Result EngineDawn::DoProcessCommands(uint32_t* texel_stride,
-                                     uint32_t* width,
-                                     uint32_t* height,
-                                     const void** buf_ptr) {
-  assert(texel_stride);
-  // TODO(dneto): Need to pass back a row_stride.
-  assert(width);
-  assert(height);
-  assert(buf_ptr);
-
+Result EngineDawn::DoProcessCommands() {
   Result result;
 
   // TODO(dneto): How to distinguish the compute case: It won't have a
@@ -368,9 +359,9 @@ Result EngineDawn::DoProcessCommands(uint32_t* texel_stride,
   // Now run the commands.
   auto command_buffer = command_buffer_builder_.GetResult();
 
-  if (render_pipeline_info_.fb_is_mapped) {
+  if (render_pipeline_info_.fb_data != nullptr) {
     fb_buffer.Unmap();
-    render_pipeline_info_.fb_is_mapped = false;
+    render_pipeline_info_.fb_data = nullptr;
   }
 
   queue_.Submit(1, &command_buffer);
@@ -379,12 +370,7 @@ Result EngineDawn::DoProcessCommands(uint32_t* texel_stride,
   DestroyCommandBufferBuilder();
 
   MapResult map = MapBuffer(device_, fb_buffer, render_pipeline_info_.fb_size);
-  render_pipeline_info_.fb_is_mapped = map.result.IsSuccess();
-
-  *texel_stride = render_pipeline_info_.fb_texel_stride;
-  *width = kFramebufferWidth;
-  *height = kFramebufferHeight;
-  *buf_ptr = map.data;
+  render_pipeline_info_.fb_data = map.data;
   return map.result;
 }
 
@@ -438,10 +424,33 @@ Result EngineDawn::CreateFramebufferIfNeeded() {
     render_pipeline_info_.fb_texel_stride = texel_stride;
     render_pipeline_info_.fb_row_stride = row_stride;
     render_pipeline_info_.fb_size = size;
-    render_pipeline_info_.fb_is_mapped = false;
+    render_pipeline_info_.fb_data = nullptr;
   }
   return {};
 }
 
+Result EngineDawn::GetFrameBufferInfo(ResourceInfo* info) {
+  assert(info);
+
+  if (render_pipeline_info_.fb_data == nullptr)
+    return Result("Dawn: FrameBuffer is not mapped");
+
+  // TODO(dneto): Need to pass back a row_stride.
+  info->image_info.texel_stride = render_pipeline_info_.fb_texel_stride;
+  info->image_info.width = kFramebufferWidth;
+  info->image_info.height = kFramebufferHeight;
+  info->image_info.depth = 1U;
+  info->size_in_bytes = render_pipeline_info_.fb_texel_stride *
+                        kFramebufferWidth * kFramebufferHeight;
+  info->cpu_memory = render_pipeline_info_.fb_data;
+  return {};
+}
+
+Result EngineDawn::GetDescriptorInfo(const uint32_t,
+                                     const uint32_t,
+                                     ResourceInfo*) {
+  return Result("Dawn:GetDescriptorInfo not implemented");
+}
+
 }  // namespace dawn
 }  // namespace amber
diff --git a/src/dawn/engine_dawn.h b/src/dawn/engine_dawn.h
index af599bb..8007321 100644
--- a/src/dawn/engine_dawn.h
+++ b/src/dawn/engine_dawn.h
@@ -63,10 +63,11 @@ class EngineDawn : public Engine {
   Result DoPatchParameterVertices(
       const PatchParameterVerticesCommand* cmd) override;
   Result DoBuffer(const BufferCommand* cmd) override;
-  Result DoProcessCommands(uint32_t* stride,
-                           uint32_t* width,
-                           uint32_t* height,
-                           const void** buf) override;
+  Result DoProcessCommands() override;
+  Result GetFrameBufferInfo(ResourceInfo* info) override;
+  Result GetDescriptorInfo(const uint32_t descriptor_set,
+                           const uint32_t binding,
+                           ResourceInfo* info) override;
 
  private:
   // Creates a command buffer builder if it doesn't already exist.
diff --git a/src/dawn/pipeline_info.h b/src/dawn/pipeline_info.h
index 8bb646c..cf4bdb3 100644
--- a/src/dawn/pipeline_info.h
+++ b/src/dawn/pipeline_info.h
@@ -49,7 +49,7 @@ struct RenderPipelineInfo {
   uint32_t fb_row_stride = 0;
   // The number of data bytes in the framebuffer host-side buffer.
   uint32_t fb_size = 0;
-  bool fb_is_mapped = false;
+  const void* fb_data = nullptr;
 
   // TODO(dneto): Record index data
   // TODO(dneto): Record buffer data
diff --git a/src/dawn/pipeline_info_test.cc b/src/dawn/pipeline_info_test.cc
index 6bc2905..a5e1a1e 100644
--- a/src/dawn/pipeline_info_test.cc
+++ b/src/dawn/pipeline_info_test.cc
@@ -49,7 +49,7 @@ TEST_F(DawnRenderPipelineInfoTest, DefaultValuesForMembers) {
   EXPECT_FALSE(static_cast<bool>(rpi.fb_buffer));
   EXPECT_EQ(0u, rpi.fb_row_stride);
   EXPECT_EQ(0u, rpi.fb_size);
-  EXPECT_FALSE(rpi.fb_is_mapped);
+  EXPECT_EQ(nullptr, rpi.fb_data);
 }
 
 }  // namespace
diff --git a/src/engine.h b/src/engine.h
index f772d27..0d6cb9f 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -33,6 +33,34 @@ enum class PipelineType : uint8_t {
   kGraphics,
 };
 
+enum class ResourceInfoType : uint8_t {
+  kBuffer = 0,
+  kImage,
+};
+
+struct ResourceInfo {
+  ResourceInfoType type = ResourceInfoType::kBuffer;
+
+  struct {
+    uint32_t texel_stride = 0;  // Number of bytes for a single texel.
+    uint32_t width = 0;
+    uint32_t height = 0;
+    uint32_t depth = 0;
+  } image_info;
+
+  // The size in bytes of Vulkan memory pointed by |cpu_memory|.
+  // For the case when it is an image resource, |size_in_bytes| must
+  // be |image_info.width * image_info.height * image_info.depth *
+  // image_info.texel_stride|.
+  size_t size_in_bytes = 0;
+
+  // If the primitive type of resource is the same with the type
+  // of actual data, the alignment must be properly determined by
+  // Vulkan's internal memory allocation. In these cases, script
+  // writers can assume that there is no alignment issues.
+  const void* cpu_memory = nullptr;
+};
+
 class Engine {
  public:
   static std::unique_ptr<Engine> Create(EngineType type);
@@ -104,11 +132,24 @@ class Engine {
   // This covers both Vulkan buffers and images.
   virtual Result DoBuffer(const BufferCommand* cmd) = 0;
 
-  // Run all queued commands and copy result data to the host.
-  virtual Result DoProcessCommands(uint32_t* stride,
-                                   uint32_t* width,
-                                   uint32_t* height,
-                                   const void** buf) = 0;
+  // Run all queued commands and copy frame buffer data to the host
+  // if graphics pipeline.
+  virtual Result DoProcessCommands() = 0;
+
+  // Get stride, width, height, and memory pointer of frame buffer.
+  // This is only valid if the buffer of framebuffer is mapped into
+  // the host address space. In particular, if we have run
+  // DoProcessCommands() and since then no graphics pipeline drawing
+  // commands have occurred e.g., DoClear, DoDrawArrays, DoDrawRect.
+  virtual Result GetFrameBufferInfo(ResourceInfo* info) = 0;
+
+  // Copy the contents of the resource bound to the given descriptor
+  // and get the resource information e.g., size for buffer, width,
+  // height, depth for image of descriptor given as |descriptor_set|
+  // and |binding|.
+  virtual Result GetDescriptorInfo(const uint32_t descriptor_set,
+                                   const uint32_t binding,
+                                   ResourceInfo* info) = 0;
 
  protected:
   Engine();
diff --git a/src/verifier.cc b/src/verifier.cc
index aac2b78..c36923d 100644
--- a/src/verifier.cc
+++ b/src/verifier.cc
@@ -114,7 +114,7 @@ Result Verifier::Probe(const ProbeCommand* command,
   return {};
 }
 
-Result Verifier::ProbeSSBO(const ProbeSSBOCommand*) {
+Result Verifier::ProbeSSBO(const ProbeSSBOCommand*, size_t, const void*) {
   return Result("Verifier::ProbeSSBO Not Implemented");
 }
 
diff --git a/src/verifier.h b/src/verifier.h
index c410d32..40610a9 100644
--- a/src/verifier.h
+++ b/src/verifier.h
@@ -30,7 +30,7 @@ class Verifier {
                uint32_t frame_width,
                uint32_t frame_height,
                const void* buf);
-  Result ProbeSSBO(const ProbeSSBOCommand*);
+  Result ProbeSSBO(const ProbeSSBOCommand*, size_t, const void*);
 };
 
 }  // namespace amber
diff --git a/src/vkscript/executor.cc b/src/vkscript/executor.cc
index ae2d43b..147eb5e 100644
--- a/src/vkscript/executor.cc
+++ b/src/vkscript/executor.cc
@@ -106,18 +106,32 @@ Result Executor::Execute(Engine* engine, const amber::Script* src_script) {
 
     for (const auto& cmd : node->AsTest()->GetCommands()) {
       if (cmd->IsProbe()) {
-        const void* buf = nullptr;
-        uint32_t width = 0;
-        uint32_t height = 0;
-        uint32_t stride = 0;
-        r = engine->DoProcessCommands(&stride, &width, &height, &buf);
+        ResourceInfo info;
+        r = engine->GetFrameBufferInfo(&info);
         if (!r.IsSuccess())
           return r;
 
-        r = verifier_.Probe(cmd->AsProbe(), stride, width, height, buf);
+        r = engine->DoProcessCommands();
+        if (!r.IsSuccess())
+          return r;
+
+        r = verifier_.Probe(cmd->AsProbe(), info.image_info.texel_stride,
+                            info.image_info.width, info.image_info.height,
+                            info.cpu_memory);
       } else if (cmd->IsProbeSSBO()) {
-        r = verifier_.ProbeSSBO(cmd->AsProbeSSBO());
+        auto probe_ssbo = cmd->AsProbeSSBO();
+        ResourceInfo info;
+        r = engine->GetDescriptorInfo(probe_ssbo->GetDescriptorSet(),
+                                      probe_ssbo->GetBinding(), &info);
+        if (!r.IsSuccess())
+          return r;
+
+        r = engine->DoProcessCommands();
+        if (!r.IsSuccess())
+          return r;
 
+        r = verifier_.ProbeSSBO(probe_ssbo, info.size_in_bytes,
+                                info.cpu_memory);
       } else if (cmd->IsClear()) {
         r = engine->DoClear(cmd->AsClear());
       } else if (cmd->IsClearColor()) {
diff --git a/src/vkscript/executor_test.cc b/src/vkscript/executor_test.cc
index 0872f9e..c177348 100644
--- a/src/vkscript/executor_test.cc
+++ b/src/vkscript/executor_test.cc
@@ -195,10 +195,11 @@ class EngineStub : public Engine {
     return {};
   }
 
-  Result DoProcessCommands(uint32_t*,
-                           uint32_t*,
-                           uint32_t*,
-                           const void**) override {
+  Result DoProcessCommands() override { return {}; }
+  Result GetFrameBufferInfo(ResourceInfo*) override { return {}; }
+  Result GetDescriptorInfo(const uint32_t,
+                           const uint32_t,
+                           ResourceInfo*) override {
     return {};
   }
 
@@ -287,10 +288,11 @@ class EngineCountingStub : public Engine {
     return {};
   }
   Result DoBuffer(const BufferCommand*) override { return {}; }
-  Result DoProcessCommands(uint32_t*,
-                           uint32_t*,
-                           uint32_t*,
-                           const void**) override {
+  Result DoProcessCommands() override { return {}; }
+  Result GetFrameBufferInfo(ResourceInfo*) override { return {}; }
+  Result GetDescriptorInfo(const uint32_t,
+                           const uint32_t,
+                           ResourceInfo*) override {
     return {};
   }
 
diff --git a/src/vulkan/compute_pipeline.cc b/src/vulkan/compute_pipeline.cc
index bfba88e..a4f94f6 100644
--- a/src/vulkan/compute_pipeline.cc
+++ b/src/vulkan/compute_pipeline.cc
@@ -81,5 +81,17 @@ Result ComputePipeline::Compute(uint32_t x, uint32_t y, uint32_t z) {
   return {};
 }
 
+Result ComputePipeline::ProcessCommands() {
+  Result r = command_->BeginIfNotInRecording();
+  if (!r.IsSuccess())
+    return r;
+
+  r = command_->End();
+  if (!r.IsSuccess())
+    return r;
+
+  return command_->SubmitAndReset(GetFenceTimeout());
+}
+
 }  // namespace vulkan
 }  // namespace amber
diff --git a/src/vulkan/compute_pipeline.h b/src/vulkan/compute_pipeline.h
index ddbc39d..ccbd1be 100644
--- a/src/vulkan/compute_pipeline.h
+++ b/src/vulkan/compute_pipeline.h
@@ -37,6 +37,9 @@ class ComputePipeline : public Pipeline {
 
   Result Compute(uint32_t x, uint32_t y, uint32_t z);
 
+  // Pipeline
+  Result ProcessCommands() override;
+
  private:
   Result CreateVkComputePipeline();
 };
diff --git a/src/vulkan/engine_vulkan.cc b/src/vulkan/engine_vulkan.cc
index d407ab7..bdcd786 100644
--- a/src/vulkan/engine_vulkan.cc
+++ b/src/vulkan/engine_vulkan.cc
@@ -272,28 +272,35 @@ Result EngineVulkan::DoPatchParameterVertices(
   return Result("Vulkan::DoPatch Not Implemented");
 }
 
-Result EngineVulkan::DoProcessCommands(uint32_t* stride,
-                                       uint32_t* width,
-                                       uint32_t* height,
-                                       const void** buf) {
-  assert(width);
-  assert(height);
-  assert(stride);
-  assert(buf);
+Result EngineVulkan::DoProcessCommands() {
+  return pipeline_->ProcessCommands();
+}
 
-  if (!pipeline_->IsGraphics())
-    return Result("Vulkan::ProcessCommands for Non-Graphics Pipeline");
+Result EngineVulkan::GetFrameBufferInfo(ResourceInfo* info) {
+  assert(info);
 
-  auto graphics = pipeline_->AsGraphics();
-  Result r = graphics->ProcessCommands();
+  if (!pipeline_->IsGraphics())
+    return Result("Vulkan::GetFrameBufferInfo for Non-Graphics Pipeline");
+
+  const auto graphics = pipeline_->AsGraphics();
+  const auto frame = graphics->GetFrame();
+  auto bytes_per_texel = VkFormatToByteSize(graphics->GetColorFormat());
+  info->type = ResourceInfoType::kImage;
+  info->image_info.width = frame->GetWidth();
+  info->image_info.height = frame->GetHeight();
+  info->image_info.depth = 1U;
+  info->image_info.texel_stride = bytes_per_texel;
+  info->size_in_bytes =
+      frame->GetWidth() * frame->GetHeight() * bytes_per_texel;
+  info->cpu_memory = frame->GetColorBufferPtr();
 
-  auto frame = graphics->GetFrame();
-  *width = frame->GetWidth();
-  *height = frame->GetHeight();
-  *stride = VkFormatToByteSize(graphics->GetColorFormat());
-  *buf = frame->GetColorBufferPtr();
+  return {};
+}
 
-  return r;
+Result EngineVulkan::GetDescriptorInfo(const uint32_t,
+                                       const uint32_t,
+                                       ResourceInfo*) {
+  return Result("EngineVulkan::GetDescriptorInfo not implemented");
 }
 
 Result EngineVulkan::DoBuffer(const BufferCommand* command) {
diff --git a/src/vulkan/engine_vulkan.h b/src/vulkan/engine_vulkan.h
index e4fd4fa..d9f82f2 100644
--- a/src/vulkan/engine_vulkan.h
+++ b/src/vulkan/engine_vulkan.h
@@ -56,10 +56,11 @@ class EngineVulkan : public Engine {
   Result DoPatchParameterVertices(
       const PatchParameterVerticesCommand* cmd) override;
   Result DoBuffer(const BufferCommand* cmd) override;
-  Result DoProcessCommands(uint32_t* stride,
-                           uint32_t* width,
-                           uint32_t* height,
-                           const void** buf) override;
+  Result DoProcessCommands() override;
+  Result GetFrameBufferInfo(ResourceInfo* info) override;
+  Result GetDescriptorInfo(const uint32_t descriptor_set,
+                           const uint32_t binding,
+                           ResourceInfo* info) override;
 
  private:
   Result InitDeviceAndCreateCommand();
diff --git a/src/vulkan/graphics_pipeline.cc b/src/vulkan/graphics_pipeline.cc
index f330e8c..c9c9eed 100644
--- a/src/vulkan/graphics_pipeline.cc
+++ b/src/vulkan/graphics_pipeline.cc
@@ -528,10 +528,6 @@ Result GraphicsPipeline::ProcessCommands() {
 void GraphicsPipeline::Shutdown() {
   DeactivateRenderPassIfNeeded();
 
-  Result r = command_->End();
-  if (r.IsSuccess())
-    command_->SubmitAndReset(GetFenceTimeout());
-
   Pipeline::Shutdown();
   frame_->Shutdown();
   vkDestroyRenderPass(device_, render_pass_, nullptr);
diff --git a/src/vulkan/graphics_pipeline.h b/src/vulkan/graphics_pipeline.h
index d9c2ef8..110d944 100644
--- a/src/vulkan/graphics_pipeline.h
+++ b/src/vulkan/graphics_pipeline.h
@@ -58,7 +58,6 @@ class GraphicsPipeline : public Pipeline {
                      VkImageAspectFlags aspect);
   VkFormat GetColorFormat() const { return color_format_; }
   VkFormat GetDepthStencilFormat() const { return depth_stencil_format_; }
-  Result ProcessCommands();
 
   Result SetClearColor(float r, float g, float b, float a);
   Result SetClearStencil(uint32_t stencil);
@@ -70,6 +69,7 @@ class GraphicsPipeline : public Pipeline {
 
   // Pipeline
   void Shutdown() override;
+  Result ProcessCommands() override;
 
  private:
   enum class RenderPassState : uint8_t {
diff --git a/src/vulkan/pipeline.h b/src/vulkan/pipeline.h
index 0b806bf..8b56391 100644
--- a/src/vulkan/pipeline.h
+++ b/src/vulkan/pipeline.h
@@ -46,6 +46,7 @@ class Pipeline {
   Result AddDescriptor(const BufferCommand*);
 
   virtual void Shutdown();
+  virtual Result ProcessCommands() = 0;
 
  protected:
   Pipeline(